I have a '99 Classic 18 stock Mercruiser 350 MAG EFI. Recently moved from Minnesota to Florida. Saturday I was out on the lake, made a high-speed run to the other side of the lake, then just floated and relaxed for about 20-30 minutes. When I decided to head home the engine would start but was missing badly and would not stay running. I opened the hatch to take a look and tried a few more times. After several minutes on the forth try it started and ran fine. I suspect vapor lock as the temp was about 95. Had not encountered that before but the boat has probably not seen that kind of ambient temp before either. Any comments or suggestions other than open the hatch on hot days?